The presentation, incidence, etiology, and treatment of surgical site infections after spinal surgery

Abstract

Study design: Descriptive, retrospective cohort analysis.

Objective: To evaluate the presentation, etiology, and treatment of surgical site infections (SSI) after spinal surgery.

Summary of background data: SSI after spine surgery is frequently seen. Small case control studies have been published reporting the results of treatment options of SSI. We performed this study to identify the most common clinical and laboratory presentation of a SSI, the most frequently seen infective organism, and evaluate the effectiveness of current treatment.

Methods: All patients who underwent spinal surgery at our institution for diagnosis other than infection between June 1996 and December 2005 (N=3174) were reviewed. All cases of SSI were identified. Patient and operative characteristics were reviewed. Infection type (deep or superficial), treatment course, laboratory and culture results were abstracted.

Results: A total of 132 cases of SSI (84 deep and 48 superficial) were identified. About 72.7% of the SSI were detected as outpatients an average 28.7 days (deep, 29.9; superficial, 25.2) after the index procedure. Wound drainage was the most common complaint (68.2%). C-reactive protein level was elevated in 98.0%, erythrocyte sedimentation rate was elevated in 94.4%, but only 48.6% had elevated white blood cell count. Staphylococcus aureus was isolated in 72.6% of deep and 85.7% of superficial positive cultures. Seventy-six percent of deep SSI could be treated with a single debridement to clear the SSI. Instrumentation was retained or primarily exchanged if loose in all cases. Around 72.9% of superficial SSI were treated without formal debridement in the operating room. Antibiotic treatment was longer in deep SSI (40.8 vs. 19.6 days).

Conclusion: Deep SSI following spinal surgery was effectively treated with single stage debridement and intravenous antibiotics. Superficial SSI could be treated effectively with local wound care and oral antibiotic therapy.